/*
 * Cay S. Horstmann & Gary Cornell, Core Java
 * Published By Sun Microsystems Press/Prentice-Hall
 * Copyright (C) 1997 Sun Microsystems Inc.
 * All Rights Reserved.
 *
 * Permission to use, copy, modify, and distribute this 
 * software and its documentation for NON-COMMERCIAL purposes
 * and without fee is hereby granted provided that this 
 * copyright notice appears in all copies. 
 * 
 * THE AUTHORS AND PUBLISHER MAKE NO REPRESENTATIONS OR 
 * WARRANTIES ABOUT THE SUITABILITY OF THE SOFTWARE, EITHER 
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A 
 * PARTICULAR PURPOSE, OR NON-INFRINGEMENT. THE AUTHORS
 * AND PUBLISHER SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED 
 * BY LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING 
 * THIS SOFTWARE OR ITS DERIVATIVES.
 */

/**
 * A class for formatting numbers that follows printf conventions.
 * Also implements C-like atoi and atof functions
 * @version 1.03 25 Oct 1997
 * @author Cay Horstmann
 */

package pogvue.util;

public class Format { /**
     * Formats the number following printf conventions.
     * Main limitation: Can only handle one format parameter at a time
     * Use multiple Format objects to format more than one number
     * @param s the format string following printf conventions
     * The string has a prefix, a format code and a suffix. The prefix and suffix
     * become part of the formatted output. The format code directs the
     * formatting of the (single) parameter to be formatted. The code has the
     * following structure
     * <ul>
     * <li> a % (required)
     * <li> a modifier (optional)
     * <dl>
     * <dt> + <dd> forces display of + for positive numbers
     * <dt> 0 <dd> show leading zeroes
     * <dt> - <dd> align left in the field
     * <dt> space <dd> prepend a space in front of positive numbers
     * <dt> # <dd> use "alternate" format. Add 0 or 0x for octal or hexadecimal numbers. Don't suppress trailing zeroes in general floating point format.
     * </dl>
     * <li> an integer denoting field width (optional)
     * <li> a period followed by an integer denoting precision (optional)
     * <li> a format descriptor (required)
     * <dl>
     * <dt>f <dd> floating point number in fixed format
     * <dt>e, E <dd> floating point number in exponential notation (scientific format). The E format results in an uppercase E for the exponent (1.14130E+003), the e format in a lowercase e.
     * <dt>g, G <dd> floating point number in general format (fixed format for small numbers, exponential format for large numbers). Trailing zeroes are suppressed. The G format results in an uppercase E for the exponent (if any), the g format in a lowercase e.
     * <dt>d, i <dd> integer in decimal
     * <dt>x <dd> integer in hexadecimal
     * <dt>o <dd> integer in octal
     * <dt>s <dd> string
     * <dt>c <dd> character
     * </dl>
     * </ul>
     * @exception IllegalArgumentException if bad format
     */

  public Format(String s) {
    width = 0;
    precision = -1;
    pre = "";
    post = "";
    leading_zeroes = false;
    show_plus = false;
    alternate = false;
    show_space = false;
    left_align = false;
    fmt = ' ';

    int state = 0;
    int length = s.length();
    int parse_state = 0;
    // 0 = prefix, 1 = flags, 2 = width, 3 = precision,
    // 4 = format, 5 = end
    int i = 0;

    while (parse_state == 0) {
      if (i >= length)
        parse_state = 5;
      else if (s.charAt(i) == '%') {
        if (i < length - 1) {
          if (s.charAt(i + 1) == '%') {
            pre = pre + '%';
            i++;
          } else
            parse_state = 1;
        } else
          throw new java.lang.IllegalArgumentException();
      } else
        pre = pre + s.charAt(i);
      i++;
    }
    while (parse_state == 1) {
      if (i >= length)
        parse_state = 5;
      else if (s.charAt(i) == ' ')
        show_space = true;
      else if (s.charAt(i) == '-')
        left_align = true;
      else if (s.charAt(i) == '+')
        show_plus = true;
      else if (s.charAt(i) == '0')
        leading_zeroes = true;
      else if (s.charAt(i) == '#')
        alternate = true;
      else {
        parse_state = 2;
        i--;
      }
      i++;
    }
    while (parse_state == 2) {
      if (i >= length)
        parse_state = 5;
      else if ('0' <= s.charAt(i) && s.charAt(i) <= '9') {
        width = width * 10 + s.charAt(i) - '0';
        i++;
      } else if (s.charAt(i) == '.') {
        parse_state = 3;
        precision = 0;
        i++;
      } else
        parse_state = 4;
    }
    while (parse_state == 3) {
      if (i >= length)
        parse_state = 5;
      else if ('0' <= s.charAt(i) && s.charAt(i) <= '9') {
        precision = precision * 10 + s.charAt(i) - '0';
        i++;
      } else
        parse_state = 4;
    }
    if (parse_state == 4) {
      if (i >= length)
        parse_state = 5;
      else
        fmt = s.charAt(i);
      i++;
    }
    if (i < length)
      post = s.substring(i, length);
  }

  /**
  * prints a formatted number following printf conventions
  * @param s a PrintStream
  * @param fmt the format string
  * @param x the double to print
  */

  public static void print(java.io.PrintStream s, String fmt, double x) {
    s.print(new Format(fmt).form(x));
  }

  /**
  * prints a formatted number following printf conventions
  * @param s a PrintStream
  * @param fmt the format string
  * @param x the long to print
  */
  public static void print(java.io.PrintStream s, String fmt, long x) {
    s.print(new Format(fmt).form(x));
  }

  /**
  * prints a formatted number following printf conventions
  * @param s a PrintStream
  * @param fmt the format string
  * @param x the character to 
  */

  private static void print(java.io.PrintStream s, String fmt, char x) {
    s.print(new Format(fmt).form(x));
  }

  /**
  * prints a formatted number following printf conventions
  * @param s a PrintStream, fmt the format string
  * @param x a string that represents the digits to print
	 * @param fmt
  */

  public static void print(java.io.PrintStream s, String fmt, String x) {
    s.print(new Format(fmt).form(x));
  }

  /**
  * Converts a string of digits (decimal, octal or hex) to an integer
  * @param s a string
  * @return the numeric value of the prefix of s representing a base 10 integer
  */

  public static int atoi(String s) {
    return (int)atol(s);
  }

  /**
  * Converts a string of digits (decimal, octal or hex) to a long integer
  * @param s a string
  * @return the numeric value of the prefix of s representing a base 10 integer
  */

  private static long atol(String s) {
    int i = 0;

    while (i < s.length() && Character.isWhitespace(s.charAt(i)))
      i++;
    if (i < s.length() && s.charAt(i) == '0') {
      if (i + 1 < s.length() && (s.charAt(i + 1) == 'x' || s.charAt(i + 1) == 'X'))
        return parseLong(s.substring(i + 2), 16);
      else
        return parseLong(s, 8);
    } else
      return parseLong(s, 10);
  }

  private static long parseLong(String s, int base) {
    int i = 0;
    int sign = 1;
    long r = 0;

    while (i < s.length() && Character.isWhitespace(s.charAt(i)))
      i++;
    if (i < s.length() && s.charAt(i) == '-') {
      sign = -1;
      i++;
    } else if (i < s.length() && s.charAt(i) == '+') {
      i++;
    }
    while (i < s.length()) {
      char ch = s.charAt(i);
      if ('0' <= ch && ch < '0' + base)
        r = r * base + ch - '0';
      else if ('A' <= ch && ch < 'A' + base - 10)
        r = r * base + ch - 'A' + 10 ;
      else if ('a' <= ch && ch < 'a' + base - 10)
        r = r * base + ch - 'a' + 10 ;
      else
        return r * sign;
      i++;
    }
    return r * sign;
  }

  /**
  * Converts a string of digits to an double
  * @param s a string
  */

  public static double atof(String s) {
    int i = 0;
    int sign = 1;
    double r = 0; // integer part
    double f = 0; // fractional part
    double p = 1; // exponent of fractional part
    int state = 0; // 0 = int part, 1 = frac part

    while (i < s.length() && Character.isWhitespace(s.charAt(i)))
      i++;
    if (i < s.length() && s.charAt(i) == '-') {
      sign = -1;
      i++;
    } else if (i < s.length() && s.charAt(i) == '+') {
      i++;
    }
    while (i < s.length()) {
      char ch = s.charAt(i);
      if ('0' <= ch && ch <= '9') {
        if (state == 0)
          r = r * 10 + ch - '0';
        else if (state == 1) {
          p = p / 10;
          r = r + p * (ch - '0');
        }
      } else if (ch == '.') {
        if (state == 0)
          state = 1;
        else
          return sign * r;
      } else if (ch == 'e' || ch == 'E') {
        long e = (int)parseLong(s.substring(i + 1), 10);
        return sign * r * Math.pow(10, e);
      } else
        return sign * r;
      i++;
    }
    return sign * r;
  }

  /**
  * Formats a double into a string (like sprintf in C)
  * @param x the number to format
  * @return the formatted string 
  * @exception IllegalArgumentException if bad argument
  */

  public String form(double x) {
    String r;
    if (precision < 0)
      precision = 6;
    int s = 1;
    if (x < 0) {
      x = -x;
      s = -1;
    }
    if (fmt == 'f')
      r = fixed_format(x);
    else if (fmt == 'e' || fmt == 'E' || fmt == 'g' || fmt == 'G')
      r = exp_format(x);
    else
      throw new java.lang.IllegalArgumentException();

    return pad(sign(s, r));
  }

  /**
  * Formats a long integer into a string (like sprintf in C)
  * @param x the number to format
  * @return the formatted string 
  */

  public String form(long x) {
    String r;
    int s = 0;
    if (fmt == 'd' || fmt == 'i') {
      if (x < 0) {
        r = ("" + x).substring(1);
        s = -1;
      } else {
        r = "" + x;
        s = 1;
      }
    } else if (fmt == 'o')
      r = convert(x, 3, 7, "01234567");
    else if (fmt == 'x')
      r = convert(x, 4, 15, "0123456789abcdef");
    else if (fmt == 'X')
      r = convert(x, 4, 15, "0123456789ABCDEF");
    else
      throw new java.lang.IllegalArgumentException();

    return pad(sign(s, r));
  }

  /**
  * Formats a character into a string (like sprintf in C)
  * @param x the value to format
  * @return the formatted string
	 * @param c
  */

	private String form(char c) {
    if (fmt != 'c')
      throw new java.lang.IllegalArgumentException();

    String r = "" + c;
    return pad(r);
  }

  /**
  * Formats a string into a larger string (like sprintf in C)
  * @param x the value to format
  * @return the formatted string
	 * @param s
  */

  public String form(String s) {
    if (fmt != 's')
      throw new java.lang.IllegalArgumentException();
    if (precision >= 0)
      s = s.substring(0, precision);
    return pad(s);
  }


  /**
  * a test stub for the format class
	 * @param a
	 */

  public static void main(String[] a) {
    double x = 1.23456789012;
    double y = 123;
    double z = 1.2345e30;
    double w = 1.02;
    double u = 1.234e-5;
    int d = 0xCAFE;
    Format.print(System.out, "x = |%f|\n", x);
    Format.print(System.out, "u = |%20f|\n", u);
    Format.print(System.out, "x = |% .5f|\n", x);
    Format.print(System.out, "w = |%20.5f|\n", w);
    Format.print(System.out, "x = |%020.5f|\n", x);
    Format.print(System.out, "x = |%+20.5f|\n", x);
    Format.print(System.out, "x = |%+020.5f|\n", x);
    Format.print(System.out, "x = |% 020.5f|\n", x);
    Format.print(System.out, "y = |%#+20.5f|\n", y);
    Format.print(System.out, "y = |%-+20.5f|\n", y);
    Format.print(System.out, "z = |%20.5f|\n", z);

    Format.print(System.out, "x = |%e|\n", x);
    Format.print(System.out, "u = |%20e|\n", u);
    Format.print(System.out, "x = |% .5e|\n", x);
    Format.print(System.out, "w = |%20.5e|\n", w);
    Format.print(System.out, "x = |%020.5e|\n", x);
    Format.print(System.out, "x = |%+20.5e|\n", x);
    Format.print(System.out, "x = |%+020.5e|\n", x);
    Format.print(System.out, "x = |% 020.5e|\n", x);
    Format.print(System.out, "y = |%#+20.5e|\n", y);
    Format.print(System.out, "y = |%-+20.5e|\n", y);

    Format.print(System.out, "x = |%g|\n", x);
    Format.print(System.out, "z = |%g|\n", z);
    Format.print(System.out, "w = |%g|\n", w);
    Format.print(System.out, "u = |%g|\n", u);
    Format.print(System.out, "y = |%.2g|\n", y);
    Format.print(System.out, "y = |%#.2g|\n", y);

    Format.print(System.out, "d = |%d|\n", d);
    Format.print(System.out, "d = |%20d|\n", d);
    Format.print(System.out, "d = |%020d|\n", d);
    Format.print(System.out, "d = |%+20d|\n", d);
    Format.print(System.out, "d = |% 020d|\n", d);
    Format.print(System.out, "d = |%-20d|\n", d);
    Format.print(System.out, "d = |%20.8d|\n", d);
    Format.print(System.out, "d = |%x|\n", d);
    Format.print(System.out, "d = |%20X|\n", d);
    Format.print(System.out, "d = |%#20x|\n", d);
    Format.print(System.out, "d = |%020X|\n", d);
    Format.print(System.out, "d = |%20.8x|\n", d);
    Format.print(System.out, "d = |%o|\n", d);
    Format.print(System.out, "d = |%020o|\n", d);
    Format.print(System.out, "d = |%#20o|\n", d);
    Format.print(System.out, "d = |%#020o|\n", d);
    Format.print(System.out, "d = |%20.12o|\n", d);

    Format.print(System.out, "s = |%-20s|\n", "Hello");
    Format.print(System.out, "s = |%-20c|\n", '!');

    // regression test to confirm fix of reported bugs

    Format.print(System.out, "|%i|\n", Long.MIN_VALUE);

    Format.print(System.out, "|%6.2e|\n", 0.0);
    Format.print(System.out, "|%6.2g|\n", 0.0);

    Format.print(System.out, "|%6.2f|\n", 9.99);
    Format.print(System.out, "|%6.2f|\n", 9.999);

    Format.print(System.out, "|%6.0f|\n", 9.999);
  }

  private static String repeat(char c, int n) {
    if (n <= 0)
      return "";
    StringBuffer s = new StringBuffer(n);
    for (int i = 0; i < n; i++)
      s.append(c);
    return s.toString();
  }

  private static String convert(long x, int n, int m, String d) {
    if (x == 0)
      return "0";
    String r = "";
    while (x != 0) {
      r = d.charAt((int)(x & m)) + r;
      x = x >>> n;
    }
    return r;
  }

  private String pad(String r) {
    String p = repeat(' ', width - r.length());
    if (left_align)
      return pre + r + p + post;
    else
      return pre + p + r + post;
  }

  private String sign(int s, String r) {
    String p = "";
    if (s < 0)
      p = "-";
    else if (s > 0) {
      if (show_plus)
        p = "+";
      else if (show_space)
        p = " ";
    } else {
      if (fmt == 'o' && alternate && r.length() > 0 && r.charAt(0) != '0')
        p = "0";
      else if (fmt == 'x' && alternate)
        p = "0x";
      else if (fmt == 'X' && alternate)
        p = "0X";
    }
    int w = 0;
    if (leading_zeroes)
      w = width;
    else if ((fmt == 'd' || fmt == 'i' || fmt == 'x' || fmt == 'X' || fmt == 'o')
             && precision > 0)
      w = precision;

    return p + repeat('0', w - p.length() - r.length()) + r;
  }

  private String fixed_format(double d) {
    boolean removeTrailing
    = (fmt == 'G' || fmt == 'g') && !alternate;
    // remove trailing zeroes and decimal point

    if (d > 0x7FFFFFFFFFFFFFFFL)
      return exp_format(d);
    if (precision == 0)
      return (long)(d + 0.5) + (removeTrailing ? "" : ".");

    long whole = (long)d;
    double fr = d - whole; // fractional part
    if (fr >= 1 || fr < 0)
      return exp_format(d);

    double factor = 1;
    String leading_zeroes = "";
    for (int i = 1; i <= precision && factor <= 0x7FFFFFFFFFFFFFFFL; i++) {
      factor *= 10;
      leading_zeroes = leading_zeroes + "0";
    }
    long l = (long) (factor * fr + 0.5);
    if (l >= factor) {
      l = 0;
      whole++;
    } // CSH 10-25-97

    String z = leading_zeroes + l;
    z = "." + z.substring(z.length() - precision, z.length());

    if (removeTrailing) {
      int t = z.length() - 1;
      while (t >= 0 && z.charAt(t) == '0')
        t--;
      if (t >= 0 && z.charAt(t) == '.')
        t--;
      z = z.substring(0, t + 1);
    }

    return whole + z;
  }

  private String exp_format(double d) {
    String f = "";
    int e = 0;
    double dd = d;
    double factor = 1;
    if (d != 0) {
      while (dd > 10) {
        e++;
        factor /= 10;
        dd = dd / 10;
      }
      while (dd < 1) {
        e--;
        factor *= 10;
        dd = dd * 10;
      }
    }
    if ((fmt == 'g' || fmt == 'G') && e >= -4 && e < precision)
      return fixed_format(d);

    d = d * factor;
    f = f + fixed_format(d);

    if (fmt == 'e' || fmt == 'g')
      f = f + "e";
    else
      f = f + "E";

    String p = "000";
    if (e >= 0) {
      f = f + "+";
      p = p + e;
    } else {
      f = f + "-";
      p = p + (-e);
    }

    return f + p.substring(p.length() - 3, p.length());
  }

  private int width;
  private int precision;
  private String pre;
  private String post;
  private boolean leading_zeroes;
  private boolean show_plus;
  private boolean alternate;
  private boolean show_space;
  private boolean left_align;
  private char fmt; // one of cdeEfgGiosxXos
}





